To be completely honest, since your boyfriend is the fish expert I think you should seperate them before a spawning happens. If your boyfriend got you hooked on fish then bettas is a good first fish. However, I think you need to start a little slower. As you said this is a new ball game and being good at baseketball doesn't mean you will survive playing football. Get used to keeping adult betta fish alive and then move into breeding.

+1...they need to be separated regardless. 2.5 gallons isn't enough for more than one betta, and males and females should never be kept together. Even if you're knowledgable about other fish, you're still learning with bettas. I highly recommend you separate them, get them happy in their own environments, and learn more before trying to spawn. It's safer for the fish, the fry and less of a headache for you.

You will have to separate them anyway since the male will become aggressive towards the female after spawning.

Bettas can have more than a couple of hundred fry, and you will need to have enough jars to separate males out from the rest of their siblings.

If your bettas are an undesirable tail type or colour, such as blue or red VTs, you will struggle to place any surviving fry in good homes. Even a lot of stores will not take them, or pay you only a pittance, and most stores that care for their bettas only want higher-end HMs and HMPKs as they can sell these for a lot more.